Nuclear reactors are fueled by radioactive materials which are compressed into pellets and installed within tubular nuclear fuel pin casings. The fuel pin casings are then plugged at the open end and sealed by welding. The completed nuclear fuel pins are assembled into bundles and the bundles are arranged within a nuclear reactor in specific configurations dependent upon the particular nuclear reactor design.
The physics of liquid metal cooled breeder reactors involves using fuel pellets containing plutonium oxide in combination with uranium oxide. The plutonium oxides used are highly toxic to humans aside from being radioactive in nature. It is therefore desirable to completely automate the production of such nuclear fuel pins so that the assembly process can occur within tightly enclosed systems and without any direct human contact.